We conducted a 24-month survey of hospital-acquired rotavirus infections in 20 renal transplant recipients who received their graft during 1988. Four cases of nosocomial rotavirus infection were diagnosed (20% of patients), 3-34 days after graft. Two patients presented with severe diarrhoea and two with fever alone. The cases occurred mainly during the winter months and remained sporadic. None of our patients was found to have chronic excretion of rotaviruses. Contacts from paediatric cases can be ruled out. We concluded that rotavirus nosocomial infections were frequent in adult renal transplant recipients and suggest that screening for rotavirus is regularly performed in these immunodeficient patients who are very susceptible to hypovolaemia.